A cool and snowy winter for the U.S.; severe weather hits Louisiana

The winter of 2010 - 2011 is in the history books, and ranks as the 39th coldest winter for the U.S. in the 116-year historical record, according to statistics released this week by the National Climatic Data Center. The cooler-than-average weather was primarily due to Arctic air spilling southwards over the eastern 2/3 of the nation due to an unusually weak Arctic Oscillation. This natural pattern in the atmosphere (whose North Atlantic version is called the North Atlantic Oscillation) allows cold air to spill southwards over the Eastern U.S., Western Europe, and East Asia when low pressure over the Arctic weakens, and high pressure over the North Atlantic also weakens. The state most affected by this unusual winter pattern was Florida, which recorded its 10th coldest winter. No other states had a top-ten coldest or warmest winter.

Figure 1. The winter of 2010 - 2011 featured colder than average temperatures over many states in the eastern 2/3 of the country, with Florida suffering its 10th coldest winter in the 116-year record. Image credit: National Climatic Data Center.

Wet in the Upper Midwest, dry in the SouthThe winter of 2010 - 2011 featured very heavy precipitation over the Upper Midwest, with South Dakota and Montana recording top-ten wettest winters. The South and mid-Atlantic were very dry, with eight states experiencing top-ten driest winters. This pattern is a typical one for a La Niña winter, since the cooler than average waters off the Pacific coast of South America act to deflect the jet stream so that the preferred track for winter storms takes them to the north over the Upper Midwest. However, the Ohio Valley typically gets above average precipitation during a La Niña winter, and that did not happen this year. This is fortunate, since very heavy rains the past two weeks have inundated Ohio, Indiana, Kentucky, and Illinois, leading to moderate flooding on many rivers.

Figure 2. The winter of 2010 - 2011 featured very heavy precipitation over the Upper Midwest, with South Dakota and Montana recording top-ten wettest winters. Image credit: National Climatic Data Center.

A snowy winter for the U.S.It was a very snowy winter for the contiguous U.S., with December, January, and February having the 7th, 5th, and 9th greatest snow extents in the 45-year record, respectively, according to the Rutgers Snow Lab. This is the 2nd consecutive very snowy winter in the U.S.; during the winter of 2009 - 2010, December, January, and February had the 1st, 7th, and 3rd greatest snow extents on record. However, an unusually early onset of spring over North America in 2010 led to April and May 2010 having the 4th lowest and 1st lowest snow extents on record for the U.S., and the snow extent numbers for North America were near average for the calendar year 2010 (Figure 3.)

Figure 3. Twelve-month running anomalies of monthly snow cover extent over Northern Hemisphere lands (including Greenland) as a whole and Eurasia and North America separately between November 1966 and December 2010. Anomalies are calculated from NOAA snow maps. Mean hemispheric snow extent is 25.0 million sq. km. for the full period of record. Monthly means for the period of record are used for 9 missing months between 1968 and 1971 in order to create a continuous series of running means. Missing months fall between June and October, no winter months are missing. Image credit: Rutgers Snow Lab.

Flooding concerns continue in the Upper MidwestThe heavy winter precipitation that hit the Upper Midwest primarily fell as snow, and recent snow water equivalent charts show that a wide swath of North Dakota, South Dakota, Minnesota, and Wisconsin have the equivalent of 4 - 6 inches of rain locked into their snowpack. If a sudden spring thaw with heavy rain occurs later this month or in early April, record or near-record flooding is likely. The latest long-range forecasts from the G FS model do not show such an event is likely to occur over the next two weeks, though. A continuation of winter-like weather over the region with below-average temperatures and light snow is expected during the coming week, with a several-day period of thawing the week of March 20. Significant melting the massive snowpack will not begin to occur until the week of March 20, at the earliest.

Tornadoes, severe thunderstorms hit the SouthA strong cold front pushing across the nation's southern states has brought severe thunderstorms, and tornado warnings have been issued for Louisiana, Mississippi, and Alabama this morning. A tornado touched down in Bush, LA at 5:20am CDT today, injuring one person and destroying one trailer. High winds from a thunderstorm hit Slidell, LA, causing roof damage, downed trees, and power outages in the city. NOAA's Storm Prediction Center has placed the region in its "Slight Risk" region for potential severe weather. You can track the action today on our severe weather page.

Sure hope the rain holds together to get SE Fla wet, we are the driest in the state this winter and need it badly!!!

See I told you Florida was record cold this past winter and last winter also! (Jan & Feb of 2010!)

It was definitely cold in Florida this past winter (though I don't know about a record; there have been at least nine other colder Florida winters). Last winter, as well--which makes it even more amazing that the year finished as tied with the warmest on record.

I hope you guys get some rain, too. We on the SW coast will try not to take it all before it gets to your side... ;-)

oooYAY -- we got RAIN - SWFL - hoping for some boomers too --been a while...been a long while.Happy for my veggie garden & fruit trees, plus all the pasture land where I work -- been buying hay bales for the past few month... this will get the grass growing!!

Between you and atmo with his "secret special radar" - I just dont know. I honestly would like to see some expertise above vagueness and questionable resume padding.

Otherwise its pretty easy, isnt it.

My own ultra top secret super-duper special unavailable-to-anyone-but-me radar shows that line of showers strengthening as it moves east into the Bay area.

Still dry here in Naples, though that obviously won't be the case for long. It's in the high 60s now; it's hard to believe--and kind of depressing to think--that it'll be 20 degrees colder this time tomorrow. I was keeping my fingers crossed that we'd seen the last of the 40s for the year, but, well, c'est la vie...

The local METS insisted the WRF weakening the squall line significantly would be wrong, and that we would get a significant line of thunderstorms.

the line did collapse

Somewhat.. Amazingly enough, a new squall line is forming in the GOM, west of Tampa. This formed out of the batch of rain in back of the squall line that had collapsed. However, here in Flagler County, we got a damage report. South Florida may have a rude awakening as the new squall line marches eastward. Folks south of Orlando will have to watch it closely.

Quoting Skyepony:Jed~ This has way more rain in it than last week's front. I've had more already & the main line isn't even here yet. Coverage is much more. It was exciting to hear thunder. Can't remember how long since I heard a solid cloud to ground before this evening.

Nice!

I am referring to West Central Florida in that context though, including the forecast.

Jed~ This has way more rain in it than last week's front. I've had more already & the main line isn't even here yet. Coverage is much more. It was exciting to hear thunder. Can't remember how long since I heard a solid cloud to ground before this evening.

Yeah, talked to my old man about that. He's a infectious disease doc up here. Obviously nobody is willing to test themselves but he's of the opinion that you guys will make it through with fairly high numbers....75-80% type range. It's gonna slash and burn through the rest though.

That would mean 90% of the population would be on Social Security. You kids better take care of yourselves. We need you.

Still have the scar on my arm. They were big shots in those days. However, they are not sure the vaccine is still effective after all these years. It was assumed it was a lifetime, but now they are not too sure.

Great. Thanks for the good news. At any rate, I'm out. Believe it or not, I found a piece of swordfish at the market today and I'm off to grill it (I know, I know - I'm nocturnal!).

Still have the scar on my arm. They were big shots in those days. However, they are not sure the vaccine is still effective after all these years. It was assumed it was a lifetime, but now they are not too sure.

Well, 'a lifetime' is a relative thing.The way things were 'back then' they did not expect us to be around today....

Glad to be of service, though you are old enough to be inoculated. Should have a nice scar from getting a version of monkeypox in you.

Still have the scar on my arm. They were big shots in those days. However, they are not sure the vaccine is still effective after all these years. It was assumed it was a lifetime, but now they are not too sure.

Ever run into these two? Both are family friends and one hell of trackers.

3RD BDE - At times the platoon sergeant of the 1st Plt of Delta Co, 2nd Bn, 12th Inf, has difficulty telling two of his troopers apart. But it is not the platoon sergeants fault, because having a set of identical twins in the platoon does cause a mixup at times.The twin brothers, PFCs Terry and Jerry Weigold of Marquette, Mich., find the mistaken identity to be nothing new to them. Beginning with their grammar school years at Marquette Elementary School, through their secondary schooling at Marquette Senior High and now the Army, their superiors have always had the same problem; Who is Who?Since being drafted into the Army in June of 1967 the brothers have served together in an identical manner.They completed basic training at Fort Campbell, Ky., after which they were both promoted to Private (E-2) on the same set of orders. After basic they were sent to Fort McClellan, Ala., for Advanced Infantry Training and were again promoted on the same set of orders to PFC upon completing their training. It was during this time that they almost had to separate and go different ways."At Fort McClellan we were told that only one of us could serve in Vietnam," said Jerry. "But Terry didn't want me to go and I didn't want him to go, so we told them we both wanted to go and here we are."Since arriving in country two months ago both of the brothers have been awarded the Purple Heart. The brothers were wounded in the same week and both were wounded in the left side by shrapnel from the same type of weapon, incoming mortar rounds.So far their tour in the Army has been identical and both brothers hope it will remain that way. But both agree that they would like to finish their tours without receiving another Purple Heart.

No, but Grothar may have, he was down South, I was up north, 23rd Inf Div, Americal, Chu Lai.

Burgess Merideth was a bank clerk and he hid in the vault on his lunch break to read his precious books. Wile he was safe in the vault reading, the a-bombs landed and he was the lone survivor. Rather than be sad, he was overjoyed to be left alone with his books...until the poor nearsighted fellow stepped on his spectacles...good stuff.

Whatever happened to the 24-hour Twilight Zone "festivals" they used to run on Thanksgiving weekend. I always enjoyed those.

Burgess Merideth was a bank clerk and he hid in the vault on his lunch break to read his precious books. Wile he was safe in the vault reading, the a-bombs landed and he was the lone survivor. Rather than be sad, he was overjoyed to be left alone with his books...until the poor nearsighted fellow stepped on his spectacles...good stuff.